part 2 Flashcards
(90 cards)
what is a population?
a group of people who are the focus of the researcher’s interest. A sample of people is taken from this
what is a sample?
a group of people who take part in a research study (participants). The sample is drawn from the target population
- the findings from the sample is then generalised across the target population
why is it important to make the sample representative of the target population?
so the psychologist can generalise the findings from their study to the general population
==> achieve this though using sampling techniques
what are the sampling types?
stratified
random
volunteer
systematic
opportunity
what is stratified sampling?
sophisticated form of sampling.
- small scale reproduction of the target population which is categorised by categorised into characteristics important to the research.h
how might stratified sampling be conducted?
- identify the strata (sub-group) that make up the population
- this is proportionate to the overall amount so it is representative and these are calculated
==> eg. if whole population has 18% of people who are make aged 30-40 then the representative sample will have 18% of people who are male aged 30-40
what is random sampling?
selecting people in a way that everyone has a fair chance of being selected
==> could be done by pulling names out of hat or using a random number generator
what is volunteer sampling / self selected sampling?
people who volunteer / chose to partake when asked or in a response to adverts
what is systematic sampling?
Selecting every nth person from a list to make a sample
==> to do this a sampling frame is made which is an organised list of people in the target people. Then researcher has to calculate how many people they need to know which nth term they need.
what is opportunity sampling?
selecting those who are most convenient, willing and available to take part there and then.
==> This could he asking people passing in the street for example
(used most by students)
what are the strengths of using stratified sampling techniques?
- the sample is representative of the target population as it is designed to accurately reflect the composition of the population. This means it’s easier to generalise to the wider population.
==> also the most representative sampling technique - Avoids researcher bias as the selection is based on the sub groups (strata) in society and randomly selected into categories once divided into strata.
what are the limitations of stratified sampling techniques?
- Time consuming in terms of knowing the subgroups and dividing the population into categories, then selecting participants to match these can be very time consuming and lots of effort.
- Researcher requires knowledge of the subgroups and categories of the population, which may not be available
Because of this, this sampling technique is not commonly used.
what are the strengths of random sampling?
- eliminates researcher bias as they have no influence over who is selected so cannot choose people who they think would support their hypothesis. Therefore more likely to create a representative sample
- more representative sample means the results are able to be generalised to the target population
what are the limitations of random sampling?
- time consuming and impractical. Not always a possibility to have alll the information on a target population or for all the target population to want to take part in the study. Thus, may end up creating a sample which is like a volunteer sample.
- may be non-representative as all of one gender could be selected randomly which would not be a true reflection of the target population
what are the strengths of volunteer sampling?
- variety of participants as they are choosing to take part
- easy and less time consuming as minimum input from the researcher is required.
- less likely to have people who want to jeopardise the study and its results (screw you / please you effect) as they have asked to take part.
what are the limitations of using volunteer sampling?
- volunteer bias, means the results will not be as generalisable as volunteers are often a certain type of person
- volunteers may be more subjected to demand characteristics as they are eager to please and they will behave how they think the researcher wants them to.
what are the strengths of using systematic sampling?
- avoids researcher bias so more likely to be a representative sample
==> means the results can be generalised to the target population
what are the limitations of using systematic sampling?
- not always truly random as the selection process can interact with a hidden periodic trait
( if every 10th person is a 19year old shop worker then they are the entire sample) - may be non-representative as all one gender could be selected randomly, which would not be a true reflection of target population.
- additionally, the strata cannot reflect all the ways people are different which makes complete representation difficult
what are the strengths of opportunity sampling?
- convenient (as it saves time, effort, and money compared to systematic and stratified) and it is a quick and easy way to get information as people are readily available.
- natural experiments use opportunity sampling as the researcher has no control who is being studied.
what are the limitations of using opportunity sampling?
- cannot generalise as the sample is likely to be unrepresentative
==> participants are drawn from one geographical area so not reflective of target population - researcher bias as they have complete control over the selection and can choose who they do and don’t want to take part.
what are the types observations
naturalistic
controlled
covert
overt
participant
non-participant
what is a covert observation?
- participants are being absorbed without their knowledge
- researcher may be physically present but pps do not know or don’t realise they’re being observed so observing natural behaviour
what is a strength and limitation of covert observation?
strength
- higher levels of validity as pps are unaware they’re being observed so eliminates demand characteristics
limitation
- unethical as doesn’t have participants informed consent
what is an overt observation?
- participants know they’re being observed
- can see the researcher observing them and are aware their behaviour is being observed an recorded for an observational study